1 // Copyright 2019 Google LLC.
2 // Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
3
4 #include "include/codec/SkCodec.h"
5 #include "include/core/SkBitmap.h"
6 #include "include/encode/SkPngEncoder.h"
7 #include "src/core/SkOSFile.h"
8
update(SkBitmap * maxBitmap,SkBitmap * minBitmap,const SkBitmap & bm)9 static void update(SkBitmap* maxBitmap, SkBitmap* minBitmap, const SkBitmap& bm) {
10 SkASSERT(!bm.drawsNothing());
11 SkASSERT(4 == bm.bytesPerPixel());
12 if (maxBitmap->drawsNothing()) {
13 maxBitmap->allocPixels(bm.info());
14 maxBitmap->eraseColor(0x00000000);
15 minBitmap->allocPixels(bm.info());
16 minBitmap->eraseColor(0xFFFFFFFF);
17 }
18 SkASSERT_RELEASE(maxBitmap->info() == bm.info());
19 const SkPixmap& pmin = minBitmap->pixmap();
20 const SkPixmap& pmax = maxBitmap->pixmap();
21 const SkPixmap& pm = bm.pixmap();
22 for (int y = 0; y < pm.height(); ++y) {
23 for (int x = 0; x < pm.width(); ++x) {
24 uint32_t* minPtr = pmin.writable_addr32(x, y);
25 uint32_t* maxPtr = pmax.writable_addr32(x, y);
26 uint8_t minColor[4], maxColor[4], color[4];
27 memcpy(minColor, minPtr, 4);
28 memcpy(maxColor, maxPtr, 4);
29 memcpy(color, pm.addr32(x, y), 4);
30 for (unsigned i = 0; i < 4; ++i) {
31 minColor[i] = std::min(minColor[i], color[i]);
32 maxColor[i] = std::max(maxColor[i], color[i]);
33 }
34 memcpy(minPtr, minColor, 4);
35 memcpy(maxPtr, maxColor, 4);
36 }
37 }
38 }
39
decode_to_srgb_8888_unpremul(const char * path)40 static SkBitmap decode_to_srgb_8888_unpremul(const char* path) {
41 SkBitmap dst;
42 if (auto codec = SkCodec::MakeFromData(SkData::MakeFromFileName(path))) {
43 SkISize size = codec->getInfo().dimensions();
44 SkASSERT(!size.isEmpty());
45 dst.allocPixels(SkImageInfo::Make(
46 size.width(), size.height(), kRGBA_8888_SkColorType,
47 kUnpremul_SkAlphaType, SkColorSpace::MakeSRGB()));
48 if (SkCodec::kSuccess != codec->getPixels(dst.pixmap())) {
49 dst.reset();
50 }
51 }
52 return dst;
53 }
54
encode_png(const char * path,const SkPixmap & pixmap)55 bool encode_png(const char* path, const SkPixmap& pixmap) {
56 if (!pixmap.addr()) {
57 return false;
58 }
59 SkPngEncoder::Options encOpts;
60 encOpts.fZLibLevel = 9; // slow encode;
61 SkFILEWStream o(path);
62 return o.isValid() && SkPngEncoder::Encode(&o, pixmap, encOpts);
63 }
64
main(int argc,char ** argv)65 int main(int argc, char** argv) {
66 SkASSERT_RELEASE(argc > 2);
67 const char* src_dir = argv[1];
68 const char* dst_dir = argv[2];
69 SkBitmap maxBitmap, minBitmap;
70 SkOSFile::Iter iter(src_dir);
71 SkString name;
72 while (iter.next(&name)) {
73 name.prependf("%s/", src_dir);
74 SkBitmap bm = decode_to_srgb_8888_unpremul(name.c_str());
75 if (!bm.drawsNothing()) {
76 update(&maxBitmap, &minBitmap, bm);
77 }
78 }
79 SkASSERT_RELEASE(sk_mkdir(dst_dir));
80 encode_png(SkStringPrintf("%s/min.png", dst_dir).c_str(), minBitmap.pixmap());
81 encode_png(SkStringPrintf("%s/max.png", dst_dir).c_str(), maxBitmap.pixmap());
82 }
83
